class_docstr: Unit tests for the evolve function
docstr: Test that the matrix of the evolved function is correct.
docstr_tok: ["Test","that","the","matrix","of","the","evolved","function","is","correct","."]
code: def test_matrix(self):
      """Test that the matrix of the evolved function is correct."""
      final_op = qml.evolve(qml.PauliX(0), coeff=2)
      mat = qml.math.expm(-1j * qml.matrix(2 * qml.PauliX(0)))
      assert qml.math.allequal(qml.matrix(final_op), mat)
  
file_path: pennylane/tests/ops/functions/test_evolve.py
imports: import warnings
  import pytest
  import pennylane
  from pennylane.ops import Evolution
  from pennylane.pulse import ParametrizedEvolution, ParametrizedHamiltonian
label_desc: Use image node_id 3 for calling the TestEvolveConstructor obj's underlying member method code with example usage: obj.test_matrix() without return types